1. Field of the Invention
This invention relates to an extendable table, that is to say a table in which the top surface can be expanded by the inclusion of one or more extension panels.
2. Description of the Related Art
There are two basic types of extendable table. In the first type, one or more extension panels are hinged to the edges of the main table panel. When an extension panel is to be used, a support rail is slid out from underneath the main table top to support the extension panel. One disadvantage of this construction is that the extension support rail is prone to break if a heavy load is placed on the extension panel. Additionally, the extension flaps hang vertically when not in use and this restricts leg room under the table.
The second type of extendable table has the extension panels provided in the centre of the table. The main table surface is provided by two sliding panels. The main panels are slid outwardly to open up a gap in the middle of the table frame where the extension panels are stowed. In one known construction, the extension panels comprise a pair of panels that are hinged together. These pair of panels must be manually lifted out of the table frame, unfolded to form a single extension surface, and then positioned in place. This known construction is inconvenient to use. The process of lifting and unfolding the extension panels is time-consuming and labour-intensive.
The invention is concerned with an improvement of the above second type of extendable table. The aim of the invention is to provide such a table which is more convenient to use and has a relatively simple construction.
In accordance with the invention, an extendable table-comprises a fixed frame, a sliding frame arranged to be slidably-movable relative to said fixed frame, a main top panel secured to said sliding frame whereby said main top panel may be pulled outwardly to open up an extension gap over said fixed frame, and an extension top panel locatable on said sliding frame and within said extension gap to form a continuous extended table surface with said main top panel, wherein said extension top panel includes first guide means interacting with said sliding frame and second guide means interacting with said fixed frame whereby, when the main top panel is pulled outwardly, the extension top panel is caused to be lifted automatically within said extension gap from a lower position below the level of the main top panel to an upper position at the level of the main top panel, and wherein the extension top panel is stowed beneath the main top panel when the extension gap is closed.
This construction provides particular convenience to the user in that the extension panel is automatically raised into position merely by sliding the main top panel. Similarly, when it is desired to return the table to its regular size, the extension panel is automatically lowered and stowed below the main top panel by a simple sliding action. There is thus no need for the user to lift or handle the extension panel at all.
In a preferred embodiment, the sliding frame consists of a pair of mutually parallel rails extending in the sliding direction. The outer ends of the rails are secured to the undersurface of the main top panel. There is a clearance gap between the main panel and the rails on the inner edge side of the main panel. The extension panel is received and stowed in this clearance gap when not in use.
The underside of the extension panel has a pair of inner guide rails in positions corresponding to those of the sliding rails and a pair of outer guide rails in positions corresponding to the outer frame members of the fixed table frame.
In the preferred embodiment, the first guide means comprises a pair of downwardly facing inclined surfaces formed on each inner guide rail. These downwardly facing inclined surfaces of the extension panels interact with corresponding upwardly facing inclined surfaces formed on the sliding rails. The second guide means comprises a slot formed on each outer guide rail of the extension panel. This slot receives a corresponding stop block formed on the inside of each table frame member. The slot and stop block are inclined at an angle to the vertical.
When the table is to be extended, the main panel is pulled outwardly. The extension panel is withdrawn from the aforementioned clearance gap beneath the main panel, as the sliding rails slip under the extension panel. The extension panel is prevented from sliding at this time by virtue of the slots in the outer guide rails receiving the stop blocks of the main frame.
As the main panel is pulled further outwardly, the inclined surfaces on the sliding rails meet the corresponding inclined surfaces of the inner guide rails. The extension panel is then forced automatically upwardly as the separation distance between the sliding rail inclined surfaces and the stop blocks is reduced. The extension panel is thus directed upwardly in a scissors action. The extension panel rides up the inclined surfaces of the sliding rails until the inner guide rails of the extension panel sit atop the sliding frame rails. At this point, the outer guide rails of the extension panel have become released from the stop blocks, so that the extension panel can be slid inwardly into intimate edgewise contact with the main panel and the centre of the table, thereby forming the extended table surface.
In the preferred embodiment, there are two sliding main panels and two extension panels. Each extension panel is linked to its associated main panel by the mechanism described above. In this way, the table can be extended optionally by different amounts with the inclusion of one or both of the extension panels. It will be appreciated, however, that in an alternative embodiment there may be one fixed main panel and one sliding main panel, with a single extension panel associated with the sliding main panel.